A Case of Benign Recurrent Intrahepatic Cholestasis Unlinked to ATP8B1 and ABCB11

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Benign Recurrent Intrahepatic Cholestasis (BRIC) is a rare genetic disorder characterized by recurring episodes of jaundice due to poor biliary flow in hepatocytes. The disease typically manifests in an autosomal recessive inheritance pattern, with average age of onset ranging from infancy to young adulthood [1]. During episodes of cholestasis, patients present with intense pruritis and jaundice that may last up to several weeks [2]. Other symptoms include nausea, vomiting, poor appetite, and steatorrhea from fat malabsorption. Laboratory evaluation usually reveals conjugated hyperbilirubinemia, elevated alkaline phosphatase (ALP), and elevated ALT/AST. Two subtypes of BRIC have been well-characterized in the literature: BRIC I, caused by mutation in ATP8B1 gene, and BRIC II, triggered by mutation in ABCB11 gene [3,4]. Both genes encode for important hepatocyte proteins involved in the flow of bile. Liver biopsies during symptomatic episodes commonly demonstrate no inflammatory hepatocanalicular cholestasis without fibrosis. In periods of remission, liver histology is normal [5]. In clinical settings, diagnosis often requires a high degree of suspicion and is confirmed by genetic testing for ATP8B1 and/or ABCB11 mutations. However, there are exceedingly rare cases of BRIC in which individuals do not have mutations in either of the associated genes. Herein, we present a case of BRIC in a 21-year-old male who demonstrated clinical, biochemical and histological evidence of disease but lacked both of the associated mutations in ATP8B1 and ABCB11.